Currently, the BS digital broadcasting uses ISDB-S (Satellite Integrated Services Digital Broadcasting) scheme.
In the ISDB-S scheme (hereafter referred to also as the current BS), one of three modulation schemes, namely, BPSK (Binary Phase Shift Keying), QPSK (Quadrature Phase Shift Keying), and 8PSK (Phase Shift Keying), can be selected for the modulation scheme in order to digitally modulate the symbols of main signals that is the primary information to be transmitted, such as image data as a program, for example.
Meanwhile, in order to execute the transmission of higher mass capacities, the upgrading of the ISDB-S scheme (thereafter referred to also as advanced BS) has been under review (refer to Non-Patent Document 1 for example).
The advanced BS allows the choice of a modulation scheme for digitally modulating main signal symbols from five modulation schemes, namely, 16APSK (Amplitude Phase Shift Keying) and 32APSK in addition to the above-mentioned BPSK, QPSK, and 8PSK, thereby enhancing the transmission efficiency.
In addition, the advanced BS uses a strong error correction code, namely, the LDPC (Low Density Parity Check) code, as a countermeasure against the errors on transmission paths that increase as the transmission efficiency is enhanced.